/* Firmware loader for Qualcomm Gobi USB hardware */

/*
 * Heavily based on the work done by mjg@redhat.com
 * 
 * Another loader?!?
 *
 * I was not able to use the Gobi Modem ( not 2k version ) of my 
 * old company Dada.net's HP EliteBook 6930p.
 * I read a lot about the Gobi modem and finally I got this loader
 * working. I did not change the way this loader send data, althought 
 * I done also some changes on it, finally I correct the sequence's bytes.
 *
 * ozw1z5rd@gmail.com
 * 
 * Copyright 2009 Red Hat <mjg@redhat.com> - heavily based on work done by
 * Alexander Shumakovitch <shurik@gwu.edu>
 *
 * crc-ccitt code derived from the Linux kernel, lib/crc-ccitt.c
 *
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include <malloc.h>

#define BLOCK_SIZE 1024*1024
//Init QDL Download
char sequence1[] = {0x01, 0x51, 0x43, 0x4f, 0x4d, 0x20, 0x68, 0x69,
                 0x67, 0x68, 0x20, 0x73, 0x70, 0x65, 0x65, 0x64, 0x20, 
                 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x63, 0x6f, 0x6c, 0x20,
                 0x68, 0x73, 0x74, 0x00, 0x00, 0x00, 0x00, 0x04, 0x04,
                 0x30, 0xff, 0xff};


//Send AMSS
char sequence2[] = {0x25, 0x05, 0x2C, 0x50, 0xA9, 0x00, 0x01, 0x00,
         0x00, 0x00, 0x04, 0x00, 0x00, 0xff, 0xff};
//Complete AMSS
char sequence3[] = {0x27, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x2C, 0x50,
         0xA9, 0x00, 0xff, 0xff};

//Send Apps
char sequence4[] = {0x25, 0x06, 0x2C, 0x60, 0x2F, 0x00, 0x01, 0x00,
         0x00, 0x00, 0x04, 0x00, 0x00, 0xff, 0xff};
//Complete Apps
char sequence5[] = {0x27, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x2C, 0x60,
         0x2F, 0x00, 0xff, 0xff};

//Complete QDL Download
char sequence8[] = {0x29, 0xff, 0xff};

/*
 * This mysterious table is just the CRC of each possible byte. It can be
 * computed using the standard bit-at-a-time methods. The polynomial can
 * be seen in entry 128, 0x8408. This corresponds to x^0 + x^5 + x^12.
 * Add the implicit x^16, and you have the standard CRC-CCITT.
 */

unsigned short const crc_ccitt_table[256] = {
    0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
    0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
    0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
    0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
    0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
    0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
    0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
    0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
    0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
    0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
    0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
    0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
    0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
    0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
    0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
    0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
    0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
    0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
    0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
    0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
    0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
    0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
    0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
    0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
    0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
    0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
    0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
    0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
    0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
    0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
    0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
    0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
};

unsigned short crc_ccitt_byte(unsigned short crc, const char c)
{
        return (crc >> 8) ^ crc_ccitt_table[(crc ^ c) & 0xff];
}

/**
 *  crc_ccitt - recompute the CRC for the data buffer
 *  @crc: previous CRC value
 *  @buffer: data pointer
 *  @len: number of bytes in the buffer
 */
unsigned short crc_ccitt(short crc, char const *buffer, size_t len)
{
    while (len--)
        crc = crc_ccitt_byte(crc, *buffer++);
    return crc;
}

void usage (char **argv) {
    printf ("usage: %s serial_device firmware_dir\n", argv[0]);
}

int main(int argc, char **argv) {   
    int serialfd,fwfd,len,qdlresplen;
    struct termios terminal_data;
    struct stat file_data;
    char *fwdata = malloc(BLOCK_SIZE);
    char qdlresp[1024];

    if (argc != 3) {
        usage(argv);
        return -1;
    }

    if (!fwdata) {
        fprintf(stderr, "Failed to allocate memory for firmware\n");
        return -1;
    }

    if ( ( serialfd = open(argv[1], O_RDWR) ) == -1) {
        perror("Failed to open serial device: ");
        return -1;
    }

    if (chdir(argv[2])) {
        perror("Failed to change directory: ");
        return -1;
    }

//Init Firmware Download
    printf("Starting Gobi firmware loader \n");
    tcgetattr (serialfd, &terminal_data);
    cfmakeraw (&terminal_data);
    tcsetattr (serialfd, TCSANOW, &terminal_data);

    *(short *)&sequence1[sizeof(sequence1)-2] = ~crc_ccitt(0xffff, sequence1, sizeof(sequence1)-2);

    write (serialfd, "\x7e", 1);
    write (serialfd, sequence1, sizeof(sequence1));
    write (serialfd, "\x7e", 1);

    printf("QDL protocol server request sent (QDL download)\n");
    qdlresplen = read (serialfd, qdlresp, 1024);
    printf("QDL protocol server response received (QDL download)\n");  

    while(qdlresp[1] == 0x0d){
        write (serialfd, "\x7e", 1);
        write (serialfd, sequence1, sizeof(sequence1));
        write (serialfd, "\x7e", 1);
        printf("QDL protocol server request sent (QDL download )\n");
        qdlresplen = read (serialfd, qdlresp, 1024);
        printf("QDL protocol server response received (bad?wait?)\n");  
    }


//Send AMSS
  printf("Device ok. Sending amss.mbn\n");

//Don't ask why you send 8 less bytes than the file, the windows driver does it as well.
// ------------------------------------------------------------------------------------
// ------------------------------------------------------------------------------------

    fwfd = open("amss.mbn", O_RDONLY);

    if (fwfd == -1) {
        perror("Failed to open firmware: ");
        usage(argv);
        return -1;
    }

    fstat(fwfd, &file_data);

    *(int *)&sequence2[2] = file_data.st_size - 8;
    *(int *)&sequence3[7] = file_data.st_size - 8;

    *(short *)&sequence2[sizeof(sequence2)-2] = ~crc_ccitt(0xffff, sequence2, sizeof(sequence2)-2);
    *(short *)&sequence3[sizeof(sequence3)-2] = ~crc_ccitt(0xffff, sequence3, sizeof(sequence3)-2);

    write (serialfd, "\x7e", 1);
    write (serialfd, sequence2, sizeof(sequence2));
    write (serialfd, "\x7e", 1);

    printf("QDL protocol server request sent (Send AMSS)\n");
    qdlresplen = read (serialfd, qdlresp, 1024);
    printf("QDL protocol server response received (Send AMSS)\n");  
    write (serialfd, sequence3, sizeof(sequence3));
    printf("QDL protocol server request sent (Complete AMSS)\n");
  
    while (1) {
        len = read (fwfd, fwdata, BLOCK_SIZE );
        printf(".");
        if (len == BLOCK_SIZE) {
            write (serialfd, fwdata, BLOCK_SIZE );
        } else {
            write (serialfd, fwdata, len-8);
            break;
        }
        write (serialfd, fwdata, 0);
    }
    printf("\nAMSS Sent.\n");
    sleep(2);

    qdlresplen = read (serialfd, qdlresp, 1024);
    printf("QDL protocol server response received (Send AMSS)\n");  
  
//Send APSS
    printf("Sending apss.mbn\n");
  
    fwfd = open("apps.mbn", O_RDONLY);

    if (fwfd == -1) {
        perror("Failed to open secondary firmware: ");
        usage(argv);
        return -1;
    }

    fstat(fwfd, &file_data);
    *(int *)&sequence4[2] = file_data.st_size;
    *(int *)&sequence5[7] = file_data.st_size;

    *(short *)&sequence4[sizeof(sequence4)-2] =
        ~crc_ccitt(0xffff, sequence4, sizeof(sequence4)-2);
    *(short *)&sequence5[sizeof(sequence5)-2] =
        ~crc_ccitt(0xffff, sequence5, sizeof(sequence5)-2);

    write (serialfd, "\x7e", 1);
    write (serialfd, sequence4, sizeof(sequence4));
    write (serialfd, "\x7e", 1);
    printf("QDL protocol server request sent (Send Apps)\n");
  
    qdlresplen = read (serialfd, qdlresp, 1024);
    printf("QDL protocol server response received (Send Apps)\n");  
  
    write (serialfd, sequence5, sizeof(sequence5));
    printf("QDL protocol server request sent (Complete Apps)\n");
  
    while (1) {
        len = read (fwfd, fwdata, BLOCK_SIZE);
        printf(".");
        write (serialfd, fwdata, len);
        if (len != BLOCK_SIZE) {
            break;
        }
        write (serialfd, fwdata, 0);
    }

    sleep(2);  

    qdlresplen = read (serialfd, qdlresp, 1024);
    printf("\nQDL protocol server response received (Complete Apps)\n");  

    printf("\nApps Sent.\n");
 
//Complete
    printf("Finishing...\n");
  
    *(short *)&sequence8[sizeof(sequence8)-2] = ~crc_ccitt(0xffff, sequence8, sizeof(sequence8)-2);

    write (serialfd, "\x7e", 1);
    write (serialfd, sequence8, sizeof(sequence8));
    write (serialfd, "\x7e", 1);
    printf("QDL protocol server request sent (Complete QDL download)\n");
    printf("Waiting 2sec to allow the device startup...\n");
    sleep(2);
    printf("Done"); 
    return 0;
}
